AMD today updated its roadmap with another multi-core processor, to slot between its dual and quad-core processors – Phenom triple-core processors. The new Phenom triple-core processors feature three processing cores on a single die and based on AMD’s Barcelona architecture, which launched last week in Opteron form.

The new triple-core processors will feature similar specifications as its upcoming Phenom X2 and X4 brethren. The Socket AM2+ processors feature 512KB of L2 cache for each core and a shared pool of L3 cache. Essentially, the Phenom triple-core processors are quad-core variants with one core disabled. This allows AMD to simply disable one core on quad-core dies for maximum use of a single wafer.

AMD claims to be the only company to offer tri-core processors, which the company claims to bring “true multi-core technology to a broader audience.” AMD has not given the Phenom triple-core processors an official name yet. However, it wouldn’t be too surprising if the tri-core processors followed the current Phenon naming scheme and received the Phenom X3 name.

“With our advanced multi-core architecture, AMD is in a unique position to enable a wider range of premium desktop solutions, providing a smarter choice for customers and end users,” said Greg White, vice president and general manager, Desktop Division, AMD. “As a customer-centric company, AMD is committed to working with our OEMs to deliver compelling value propositions across their multi-core product families with capabilities that address their requirements and aspirations.”

Features unique to AMD’s Barcelona and Stars architectures such as split power planes and dynamic independent core speed adjustments remain supported on triple-core processors. Additionally, AMD Phenom triple-core processors support HyperTransport 3.0 for up to 16GB/second of I/O bandwidth.

AMD claims significant performance gains over dual-core processors with its triple-core processors in benchmarks such as SYSmark 2007 and 3DMark06, where gaming and digital content creation performance is key.

“A continued commitment to elegant design and innovative processor architecture is instrumental to revolutionizing the technology industry,” said Richard Shim, research manager for IDC's Personal Computing program. “The advent of triple-core processors is a valuable market opportunity for customers to deliver end users compelling solutions and further differentiate on the desktop.”

It will cost AMD the same amount to manufacture a tri-core CPU as a quad-core CPU so it seems like AMD will loose potential revenue with every tri-core CPU sold.

Sure it costs the same thing to manufacture a triple core as it does a quad core. But selling those triple cores is better than throwing them away.

When cores are manufactured, they are placed into CPU packages depending on several variables, like processor supply and demand, cost, and most importantly, which CPU's pass certain QC tests. Take Intel for example. The core from a Celeron 400 series and a C2D extreme are manufactured the same way, but the core that eventually became a Celeron only passed very few of the QC tests and the core that became an Extreme passed several high stress QC tests. That's basically what it means when you see "such and such processor with this much cache disabled". Why throw the chips away if they can still be used, even if it's not at their top efficiency. That's why Intel pushed themselves to get rid of single core P4s, 800 and 900 series processors and 300 series Celerons. Their fab process is way more efficient now that they basically manufacture the same chips over and over.

If bench tests are good for the tri-cores, you'll probably see Intel put them out too.